#22 Checking in - 1/48 Sierra Consolidated PB-2 vac-form

[jimmaas]

With a bit of trepidation, I'm going to attempt my first Group Build (while admitting glaciers move faster).  Haven't cut plastic but have been gathering references on this less-than-stellar fighter (the designation means 'Pursuit Biplace') in the glorious tradition of the Roc, Defiant, and other fighters that somehow needed a gunner in the back.

 

 

 

 

[Mjwomack]

Welcome to Groupbuilds @jimmaas and we're flattered that you chose us. Your hosts have a duty of care and full disclosure approach to please be warned that GBs are surprisingly addictive. What Joe Walsh meant to sing was

I stay at Groupbuilds, sometimes until 4, it's hard to leave when you can't find the door. The Eagles also touched upon this in Hotel Enzoarna (Facebook Fact every one of them).

 

Some like a bit of resin, but I'm always happy to see some vac-form being formed! Sadly, I can't see the photo- I assume this is the box art. Can anyone see it please?

If it turns out to be at your end of the electric string, this is a really good guide

It must be good because it worked for me!

 

think I've found a review of it now

 

https://archive.aeroscale.net/review/218/index.htm 

 

And might even have found it in Sclaemates

https://www.scalemates.com/kits/sierra-scale-models-48-23-consolidated-aircraft-p-30--1076318 

 

 

And I may have been very generous to talk of 'box' art; a very positive review though so look forward to seeing it progress and a whole new one to me.

 

Remember cutting out doesn't count as part of the build and up to 25% of the build is permitted in any case, so feel free to take full advantage of that and move that glacier along

 

[jimmaas]

 

[Mjwomack]

Brilliant, I can see it now thanks 👍 

[Colin W]

Fantastic stuff. You really should save this for the 'Worst Manufacrurers' Group Build or someting like that. One of the 2 kits that I have binned over the last 30 years was my only Sierra Kit. The 1/48 Fairly Barracuda. Distorted and out line with a solid lump of flash with bits in it resembling wheels and other aeroplane parts. The same white plastic you have in the zippy bag. Total rubbish. I had it in the stash until Special Hobby released their effort then I binned it. I did retain the decals though, some of which I used on the final SH Baracuda. 

 

Good luck with this and I hope you enjoy a challenge!. 

 

[jimmaas]

Well, start of the project, and a few items cut off the backing

but one of the things I noticed is that the gun troughs were a bit indistinct.  So, measure out areas to cut out and insert plastic tubing

 

and once the tubing goes in, seal the edges with superglue and let set.  When dry, we'll see if sanding down the tubing will yield a proper trough.

 

[jimmaas]

Okay then!  Cut back the tubing insert, sand down, and voila - a neater trough.  Previous, less defined trough, shown first for comparison.

 

[Mjwomack]

Excellent start 👍 

[heloman1]

A neat start...

[2996 Victor]

Great start, Jim, the gun trough work is first class. I had one of these kits, wish I'd kept it now!

 

Looking forward to your next update.

 

Cheers,

Mark

[JOCKNEY]

Any vacform kit ticks all the boxes for me, you don't so much build it, as create it !

 

The injection parts look familiar to a Donetsk Toy Factory kit i have where the parts were almost see through.  Apparently this is due the the plastic not having certain elements added during the process, or so I was told.

 

Best of luck with the build 

 

Cheers Pat 

[jimmaas]

Plodding along (this GB end in November of WHAT year again?) with more clarification of the nose/engine details.  First, the exhaust stack area is indicated by a shallow indentation, where photos show a sharp edge, so carefully cut out a rectangle on each side (Wilkinson razor blades work a treat!) and insert a channel made up of plastic strip.

 

 

[jimmaas]

Next, the bulge on the port side of the nose is a fairing for the turbocharger, but instead of closed at front and back as in the vacuform, it had an open in both locations. So, more slicing and off comes the bulge, and a bit of fettling to create a blank to fill the hole.

[AdrianMF]

Great set of improvements to the kit so far! The turbocharger installation looks interesting too.

 

Regards,

Adrian

[jimmaas]

One of the distinctive elements of the PB-2 was the honking huge turbocharger installation on the port nose.  The Sierra kit provides resin or injection parts (I'm not sure quite what they're made from) for the exhaust/turbo system but the exhaust ports leading into the manifolds are poorly defined.  So the exhaust pipes were removed from the back of the manifold and replaced by better defined resin bits from a Classic Airframes P-6E kit.  Appropriate keying pegs were added

and the fairings forward and aft of the turbine wheel were cleaned up and flat locating keys were made up.  After a lot of trial and error (and I was found guilty several times!) the two pieces were primed for later metallizing.

 

[jimmaas]

On to the tailplanes.  A lot of sanding involved, to avoid the #1 tip-off of vacuform origin - thick trailing edges!

 

 

The nature of the fairings around the tailplanes make it necessary to open fairing=shaped holes in the fuselage halves, and c-a-r-e-f-u-l-l-y file the openings to fit the outlines of the tailplane fairings.  

 

 

The fit has to be pretty close, and the base will eventually be glued from the inside.

 

 

Now the elevators can be separated, with hinge pins (and some locating keys) and the rod connecting the elevators (which goes into the fuselage) added.  Some cleanup still to go.

 

[2996 Victor]

Superb, exacting work, Jim, you're making fine progress on this project!

 

Cheers,

Mark

[Malc2]

Ooh, love a vacform, especially one of a plane I have never heard of!

Looking good.

Malc.

[JOCKNEY]

Looks the business Jim, keep it up mate 

 

Cheers Pat

[jimmaas]

Once the engine externals and tailplanes are done, it's time to grip the reins and head for the interior...with a whole lot of guesswork.  The kit comes with sidewalls and a floorboard, but as with any vacuform, the tolerances are a bit dodgy.  The top decking is also a bit vague, since there's a big opening on the decking bit aft of the pilot's position.  In addition, I am worried about the fit (widthwise) of the canopy.  So, I cobbled together two pieces for the top decking the more closely matched the photos.

 

Then a cheap and chippy chop-job to the existing decking, to proceed with the sidewalls.

 

 

Sidewall glued in place, the next step is the floorboard, which will be structurally important.  I used some Evergreen .060 channel plastic strip to provide a locating guide on the starboard side.

 

 

Once satisfied, a similar channel was added on the port side.  Using the kit part as a guide (but making it a little wider) the rear floor piece was test fitted and, after some mods, glued in on the starboard side.

 

[Magpie22]

Jim,

I'm watching this build with great interest. I have the kit and even contemplated doing it for this group build. 

Now I will record your work and use it when I do my own build.  

Peter M

[jimmaas]

Starting place for the cockpit is the instrument panel and adjacent equipment.  The Sierra kit gives an injected panel which is a good starting point, but can be better defined with some scratch building.  Using the kit piece, the location is defined so a solid 'backboard' can be crafted to attach to new panel to.

 

The instrument panel itself is a boxy center panel, with the back end of the machine gun receivers on either side,  These aren't shown in the photos, but this was a standard setup for period USAAC aircraft (think P-36 and P-40).  The panel itself, luckily, looks almost exactly like the central instrument group from the P-40, for which there are a number of aftermarket options available.

 

Here, the composite instrument panel (the rudder pedals have yet to be added) is seen along with the backboard it will attach to.

 

 

[Mjwomack]

On 6/23/2025 at 8:07 PM, jimmaas said:

With a bit of trepidation, I'm going to attempt my first Group Build (while admitting glaciers move faster). 

 

Really? You're setting quite a pace for a glacier and at an amazing level of detail.

[jimmaas]

...and couldn't wait to finish off the instrument panel - the center part of the Hawk 75 panel works out great!

 

[jimmaas]

The past week has been a time of little fiddles - lightening hole structure, addition of retraction gear crank column, pilots map bin, etc.

 

But it's time for one of the riskier steps.  Under the engine is a housing for the radiator and oil cooler.  Unfortunately, the radiator opening crosses the centerline, which makes working on it difficult until the fuselage halves are joined, and once that happens accessing the interior becomes a problem. 

 

So the compromise solution is to join the parts of the fuselage halves for the housing only, and then cutting the housing away (Wilkinson razor blades work superbly with vacuform plastic!).